1. Field of the Invention
The invention relates to linear tape drive modules for linear tape drive systems.
2. Discussion
Linear tape drive systems may include a tape that has data transitions perpendicular to a path direction of the tape and a pre-recorded servo track having angled transitions relative to the data transitions. Data elements may run parallel to the data transitions and a servo element may run across the angled transitions. By indexing across the width of the tape, the servo allows a head to serpentine within a plurality of defined data bands.
A data read element may be 50% of the width of a written track thus allowing for “off track” wander without intercepting the adjacent written track data. The over-sizing of the written track to compensate for off track wander may limit the number of tracks that can be packed across the width of the tape while keeping the magnetic read element width such that a useful signal may be reliably generated.
Helical scan drives may include several independent single track heads mounted on an angle in a rotating drum which spins in the direction of tape motion without the use of an active servo positioning system reference to the tape. While helical scan drives may have lower data rates due to low read/write element count and lower linear data density, it may offer the advantage of packing tracks horizontally on tape next to, or over lapping, each other due to the data signal cancelling realized when a read element is parallel to the desired track transition and up to perpendicular to the adjacent track transition. This allows the read element to be up to the same size as the written track to increase signal output and maximize horizontal track packing.